In the art of drain and sewer cleaning equipment the so-called plumbers snake or sewer augering apparatus is a well known expedient for clearing pipes of all sorts of obstructions. The apparatus typically comprises an elongated flexible snake, commonly in the form of an elongated tightly coiled spring, which is wound in a rotary canister for feeding of the snake from a suitable feed aperture or opening which is normally positioned on the axis of rotation of the canister.
In some snake apparatus, the snake is fed manually from the canister by simply pulling a desired length of the coiled snake from the canister opening. The incremental length of snake is then manually fed into the pipe or drain to be cleaned in conjunction with rotation of the canister, which in turn rotates the snake extending therefrom. When withdrawing a length of snake from a pipe, it is manually pushed back into the canister through the access opening whereupon the snake spontaneously forms into successive coils within the canister.
Other plumbers snake apparatus is known which incorporates a power feed in the form of rollers or similar drive elements that engage the exterior surface of the snake, but which at the same time are not rotatable about the axis of rotation of the canister. The rollers typically may be rotatable independently about respective axes of rotation which extend in non-parallel relation with respect to the axial extent of the snake element. Thus, as the canister and snake element are rotated, the feed rollers or other such guide elements in engagement with the exterior periphery of the snake element trace a spiral path in the axial direction along the snake element. Since the guide rollers are held axially stationary, the result is that the snake element is subjected to powered feed from the canister and into the drain or pipe to be cleared.
For both powered and manual feed plumbers snakes, the rotation of the canister and snake element serves to rotate an auger bit, cutter or other drain clearing element mounted at the forwardmost end of the snake whereby the rotating bit dislodges and clears obstructions encountered as the fowardmost end of the snake is fed through the drain or pipe.
Also known in the art are manual lock mechanisms for manual feed plumbers snakes which serve to grip the snake and retain it against unintended infeed or outfeed to or from the canister during operation. Such lock mechanisms have included spring loaded, radially moveable tab elements which are moved radially into and out of engagement with the snake element as desired in operation. Such lock mechanisms permit manual feed pressure to be applied axially on the snake during operation to thereby force the leading end of the snake element through the pipe. Without a lock mechanism, such axial force would tend to feed the snake backwards into the canister rather than forward into the drain or pipe.
The following patents disclose some of the above and various other aspects of known plumbers snake and similar apparatus: U.S. Pat. Nos. 3,394,599, 3,451,089, 3,451,090, 3,224,024, 3,449,782, 3,609,788, 3,093,854, 3,246,354 and 3,691,583.
Notwithstanding the variety of known plumbers snake apparatus developed hitherto, practitioners of the art have continually sought improvements to provide greater ease and reliability of operation, simplification of design structure, and ways of combining desirable operational features for convenient application and use in relatively small and simple structural packages.